Assessing worm burdens with diagnostics

Assessing worm burdens with diagnostics
The advantages of diagnosticled treatment
Diagnosticled treatment utilises faecal egg counts FECs and antibody tests either via saliva or blood preferably with a yearly risk assessment from a vet to inform the need for worming treatment. It has been shown to delay resistance development with the largest delays shown in temperate climates 1
Available diagnostic tests
Faecal worm egg count FEC
Faecal egg counts FECs are an important tool for worm control. They measure the number of worm eggs contained in a sample of your horses dung to indicate the level of eggshedding and whether or not your horse may need a wormer.

Parasite life cycles are linked to the seasons. The life cycle of most worms involves the horse inadvertently ingesting infective larvae from the pasture. These develop into adults in the horses digestive system and eggs are released and excreted shed via droppings.
When should I conduct FECs?
Wet and warm spring or summer months present the ideal environmental conditions for the development of eggs and larvae on the pasture. This can lead to high pasture contamination and increase the potential for horses to acquire new parasite burdens predominantly small redworms. It is why regular faecal egg counts FECs every 812 weeks from March to October are so important 2 \
How do I conduct an FEC?
Collect a small sample of fresh dung from your horse. Because worm eggs are distributed unevenly within each pile of droppings it is best to collect a small pinch from at least five different faecal balls within a single dung pile. 
Droppings used should be less than four hours old at the time of collection and the sample should be transferred to a plastic bag with as much of the air expelled as possible or filled to the top of an airtight container.
Samples should be kept cool and sent to a laboratory or your vet for testing as soon as possible to prevent any eggs hatching prior to counting.
At the laboratory or vet practice
There are a many different ways in which an FEC may be carried out a commonly used method is the McMaster technique. At the laboratory the dung samples will be mixed with a flotation fluid and large clumps such as grass hay or straw will be filtered out. The sample is centrifuged and the solid particles will settle to the bottom whilst the eggs